Appellant was charged with illegal sale of shabu in an Information dated 18 July 2003, committed as follows:

That on or about the 16th day of July 2003 in Caloocan City, M.M. and within the jurisdiction of this Honorable Court, the above-named accused, conspiring together and mutually helping one another, without having been authorized by law, did then and there wil[l]fully, unlawfully and feloniously sell and deliver to one PO2 EUGENE C. AMOYO, who posed as buyer, two (2) pcs. of small transparent plastic sachets containing 0.08 gram, total weight of Methylamphetamine Hydrochloride (shabu) for [t]wo (2) pcs of One Hundred Peso Bill with SN DF950395 and KY384741 knowing the same to be a dangerous drug.

Appellant entered a plea of not guilty upon arraignment. During the pre-trial conference, the parties stipulated that P/Insp. Ericson L. Calabocal conducted a qualitative examination on two (2) heat-sealed transparent plastic sachets evidenced by Physical Science Report No. D-845-03 dated 17 July 2003. It was further stipulated that said witness had no personal knowledge as to the facts and circumstances surrounding the arrest of appellant, as well as the source of the subject specimens.4

Trial ensued. Witnesses for the prosecution narrated that in the evening of 16 July 2003, a male informant came to the office of the Northern Police District on Tanigue Street, Kaunlaran Village, Caloocan City. In the presence of PO3 Gilbert Velasco (PO3 Velasco) and PO2 Eugene Amoyo (PO2 Amoyo), the informant complained about the rampant selling of shabu by a certain Mac-Mac. Said information was relayed to P/Chief Inspector Rafael Santiago who immediately instructed PO3 Velasco to form a buy-bust team. The team was composed of PO3 Velasco, PO2 Amoyo, PO3 Joel Borda (PO3 Borda), PO2 Loreto Lagmay, PO1 Renato Ameng, PO1 Allan Reyes and PO1 Joel Cosme. PO2 Amoyo was the designated poseur-buyer. Two (2) pieces of P100.00 bills were prepared as boodle money. The initials "ECA" were placed on the bills.

The buy-bust team underwent a briefing and then proceeded to the target area on board two (2) separate vehicles. They arrived at a parking lot along Hipon Liit in Dagat-dagatan at 7:30 p.m. PO2 Amoyo, PO3 Velasco and PO3 Borda, along with the informant, waited beside a coconut tree for Mac-Mac.

After two hours, appellant arrived with two male companions. The informant approached appellant and introduced PO2 Amoyo to him as a buyer of P200.00 worth of shabu. Appellant left for a while to get the shabu from his companions, who were standing 7 meters away from the group. He returned ten (10) minutes later and handed two (2) plastic sachets to PO2 Amoyo, who, in exchange, handed over the boodle money.

After the exchange, PO2 Amoyo raised his left hand to signal the other members of the buy-bust team that the transaction had already been concluded. PO3 Velasco and PO3 Borda immediately arrested appellant while PO2 Amoyo ran after appellant's companions. There was an exchange of gunfire between PO2 Amoyo and an unidentified companion but the latter was able to escape unscathed. PO2 Amoyo kept the two (2) plastic sachets in his pocket.

A spot investigation was conducted on appellant. It was revealed that the two (2) male companions were identified as Amay and Tabo. Appellant was then brought to the police headquarters. PO2 Amoyo placed his markings "ECA-BB-1" and "ECA-BB-2" on the plastic sachets before turning them over, together with the buy-bust money, to SPO4 Jorge Tabayag. PO2 Amoyo also prepared a request for laboratory examination addressed to the Philippine National Police (PNP) Crime Laboratory.

The two (2) plastic sachets containing white crystalline substance were found positive for shabu. Said finding was indicated in Physical Science Report No. D-845-035 prepared by Forensic Chemist and Police Inspector Erickson L. Calabocal of the PNP Crime Laboratory Group.

Appellant presented a different version of the facts. He testified that at 8:30 p.m. on 16 July 2003, he was sitting in the plaza located on Hipon Liit St., Dagat-dagatan, Caloocan City. He was waiting for his brother to deliver his boots when the policemen arrived and were looking for an alias Amay. Appellant then heard a gunshot and saw Amay firing the shot. Appellant ran towards his house. Later, the policemen went to his house and handcuffed him. When appellant asked why he was being arrested, the policemen claimed that appellant knew Amay. Appellant denied selling shabu and asserted that the case was filed against him when he refused to give information about Amay.

Appellant's testimony was corroborated by his brother, Balweg Dela la Cruz, who stated in court that appellant instructed him to get his boots and bring them to the plaza at around 8:30 p.m.6 As he was about to leave the house, Balweg saw his brother being arrested by two policemen. He heard from other people that the policemen were asking appellant if he knew of a man named Amay.7

In finding appellant guilty, the trial court ruled that there was a meeting of minds between the poseur-buyer and appellant as to the delivery of shabu in exchange for P200.00. The dispositive portion of said judgment reads:

Premises considered, this Court finds accused MARK DELA CRUZ Y BATAC "GUILTY" beyond reasonable doubt for Violation of Sec. 5, Article II of [R.A. No.] 9165, otherwise known as the Comprehensive Dangerous Drugs Act of 2002 and imposes upon him the penalty of Life Imprisonment and a fine of Five Hundred Thousand (P500,000.00) Pesos.

The two (2) plastic sachets containing 0.04 gram each of Methylamphetamine Hydrochloride is hereby ordered confiscated in favor of the government to be turned over to the Philippine Drug Enforcement Agency (PEDEA) [sic] for proper disposition.

On 15 September 2006, appellant appealed to the Court of Appeals via a notice of appeal.9

On 12 September 2007, the Court of Appeals rendered judgment affirming the RTC's decision in Criminal Case No. 68601.10 The appellate court gave weight to the testimony of the poseur-buyer as well as to the Physical Science Report in concluding that the illegal sale of shabu was perpetrated by appellant. The appellate court rejected appellant's defense of frame-up for failure to substantiate such allegation and in light of the presumption of regularity accorded to police officers in the performance of their official duties. Anent the alleged failure of the police officers to observe the procedure laid down under Section 21 of R. A. No. 9165, the appellate court held that such failure is not fatal as the circumstances in the instant case show that the integrity pertaining to the custody of the seized shabu was not compromised notwithstanding that the same were marked only during the investigation held at the police station.11

After obtaining an unfavorable decision, appellant filed a notice of appeal before this Court.12

On 9 April 2008, this Court required the parties to simultaneously file their supplemental briefs.13

In two separate manifestations, both parties expressed their intention not to file any supplemental brief since all the issues and arguments have already been raised in their respective Briefs.14

Appellant maintains that the prosecution was not able to establish the moral certainty required by law to prove his guilt beyond reasonable doubt. He contends that his defenses of alibi and denial were supported not only by his testimony but by that of other witnesses. He questions the identity of the shabu allegedly confiscated from him as the marking was made only in the police station in front of the investigating officer, contrary to the requirement laid down in Section 21 (1) of RA No. 9165. He also assails the forensic laboratory examination result in that it was not covered by a certification in violation of Section 21 (3) of the same law. He stresses that the prosecution must not simply rely on the presumption of regularity for it cannot by itself support a judgment of conviction.15

In its appellee's brief,16 the Office of the Solicitor-General (OSG) supports the conviction of appellant. It argues that appellant was caught in flagrante delicto selling shabu in a legitimate buy-bust operation. It claims that the elements necessary in the prosecution of the illegal sale of drugs were duly established by the prosecution, namely: the appellant, as seller of the shabu, and the poseur-buyer were identified; and the shabu confiscated from appellant and the money used to buy it were also presented in court. The OSG emphasizes that the sachets of shabu presented in court were the same sachets confiscated from appellant and subjected to laboratory examination. It justifies the non-observance of Section 21 (1) of R. A. No. 9165 since the corpus delicti of the illegal sale of drugs was duly established during trial. It adds that after the confiscation of the sachets of shabu from appellant, they were immediately submitted for laboratory examination to the PNP Crime Laboratory.17

The appeal is meritorious.

The elements necessary for the prosecution of illegal sale of drugs are: (1) the identities of the buyer and the seller, the object, and consideration; and (2) the delivery of the thing sold and the payment therefor. What is material to the prosecution for illegal sale of dangerous drugs is the proof that the transaction or sale actually took place, coupled with the presentation in court of evidence of corpus delicti.18

The common issue that crops out of a buy-bust operation, like in this case, is whether the drug submitted for laboratory examination and presented in court was actually recovered from appellant. The Court is cognizant of the fact that an entrapment operation is open to possibilities of abuse. It is by this same thrust that the chain of custody rule was adopted by the Court. In Lopez v. People,19 we had the occasion to expound on the chain of custody rule, thus:

As a method of authenticating evidence, the chain of custody rule requires that the admission of an exhibit be preceded by evidence sufficient to support a finding that the matter in question is what the proponent claims it to be. It would include testimony about every link in the chain, from the moment the item was picked up to the time it is offered into evidence, in such a way that every person who touched the exhibit would describe how and from whom it was received, where it was and what happened to it while in the witness' possession, the condition in which it was received and the condition in which it was delivered to the next link in the chain. These witnesses would then describe the precautions taken to ensure that there had been no change in the condition of the item and no opportunity for someone not in the chain to have possession of the same.

While testimony about a perfect chain is not always the standard because it is almost always impossible to obtain, an unbroken chain of custody becomes indispensable and essential when the item of real evidence is not distinctive and is not readily identifiable, or when its condition at the time of testing or trial is critical, or when a witness has failed to observe its uniqueness. The same standard likewise obtains in case the evidence is susceptible to alteration, tampering, contamination and even substitution and exchange. In other words, the exhibit's level of susceptibility to fungibility, alteration or tampering without regard to whether the same is advertent or otherwise not dictates the level of strictness in the application of the chain of custody rule.

Indeed, the likelihood of tampering, loss or mistake with respect to an exhibit is greatest when the exhibit is small and is one that has physical characteristics fungible in nature and similar in form to substances familiar to people in their daily lives. Graham v. State positively acknowledged this danger. In that case where a substance later analyzed as heroin was handled by two police officers prior to examination who however did not testify in court on the condition and whereabouts of the exhibit at the time it was in their possession was excluded from the prosecution evidence, the court pointing out that the white powder seized could have been indeed heroin or it could have been sugar or baking powder. It ruled that unless the state can show by records or testimony, the continuous whereabouts of the exhibit at least between the time it came into the possession of police officers until it was tested in the laboratory to determine its composition, testimony of the state as to the laboratory's findings is inadmissible.

A unique characteristic of narcotic substances is that they are not readily identifiable as in fact they are subject to scientific analysis to determine their composition and nature. The Court cannot reluctantly close its eyes to the likelihood, or at least the possibility, that at any of the links in the chain of custody over the same there could have been tampering, alteration or substitution of substances from other cases'by accident or otherwise in which similar evidence was seized or in which similar evidence was submitted for laboratory testing. Hence, in authenticating the same, a standard more stringent than that applied to cases involving objects which are readily identifiable must be applied, a more exacting standard that entails a chain of custody of the item with sufficient completeness if only to render it improbable that the original item has either been exchanged with another or been contaminated or tampered with.

Thus, the corpus delicti should be identified with unwavering exactitude.20

This Court believes that the prosecution failed to clearly establish the chain of custody of the seized plastic sachets containing shabu from the time they were first allegedly received until they were brought to the police investigator.

PO2 Amoyo testified that he failed to place any marking on the sachets of shabu immediately after the apprehension of appellant. In fact, PO3 Amoyo admitted that he only placed his markings upon being ordered by SPO4 Tabayag.21

The defense however failed to corroborate PO2 Amoyo's claim. While SPO4 Tabayag was presented in court, he neglected to mention nor was he asked about the markings on the shabu. On the contrary, the sworn statement of PO2 Amoyo, which was formally offered in evidence, seemed to suggest that markings were made prior to the submission of the shabu to SPO4 Tabayag, to wit:

Verily, PO2 Amoyo's testimony suggests that he already placed his markings prior to being questioned by SPO4 Tabayag.

Moreover, no other witness was presented to testify or to fill the gap from the time SPO4 Tabayag received the sachets of shabu from PO2 Amoyo up to the time they were delivered to the PNP Crime Laboratory.

Furthermore, nothing on record shows that the procedural requirements of Section 21, Paragraph 1 of Article II of R. A. No. 916523 with respect to custody and disposition of confiscated drugs were complied with. There was no physical inventory and photograph of the items allegedly confiscated from appellant. Neither did the police officers offer any explanation for their failure to observe the rule. The prosecution merely sought refuge in its belief that a stringent application of the rule may be dispensed with if the corpus delicti has been duly established.

In People v. Orteza,24 the Court citing People v. Laxa,25People v. Kimura26 and Zarraga v. People,27 reiterated the ruling that the failure of the police to comply with the procedure in the custody of the seized drugs raises doubt as to its origins.28

In People v. Nazareno,29 the poseur-buyer failed to immediately place his markings on the seized drugs before turning them over to the police investigators. The police officer who placed his markings was not presented to testify on what actually transpired after the drugs were turned over to him. The Court equated these circumstances as failure on the part of the prosecution to prove the existence of the corpus delicti.30

As stated by the Court in People v. Santos, Jr.,31 failure to observe the proper procedure also negates the operation of the presumption of regularity accorded to police officers.32 As a general rule, the testimony of the police officers who apprehended the accused is usually accorded full faith and credit because of the presumption that they have performed their duties regularly.33 However, when the performance of their duties is tainted with irregularities, such presumption is effectively destroyed.

While the law enforcers enjoy the presumption of regularity in the performance of their duties, this presumption cannot prevail over the constitutional right of the accused to be presumed innocent and it cannot by itself constitute proof of guilt beyond reasonable doubt.34 The presumption of regularity is merely just that a mere presumption disputable by contrary proof and which when challenged by the evidence cannot be regarded as binding truth.35

In fine, the failure to establish the corpus delicti is detrimental to the cause of the prosecution. The Court is thus constrained to acquit appellant on reasonable doubt.

WHEREFORE, the assailed Decision of the Court of Appeals dated 12 September 2007 affirming the judgment of conviction of the Regional Trial Court of Caloocan City, Branch 120 is REVERSED and SET ASIDE. Appellant MARK DELA CRUZ y BATAC is ACQUITTED on reasonable doubt and is accordingly ordered immediately released from custody unless he is being lawfully held for another offense.

The Director of the Bureau of Corrections is ORDERED to implement this decision forthwith and to INFORM this Court, within five (5) days from receipt hereof, of the date appellant was actually released from confinement.

Let a copy of this decision be forwarded to the PNP Director and the Director General of the Philippine Drug Enforcement Agency for proper guidance and implementation. No costs.

(1) The apprehending team having initial custody and control of the drugs shall, immediately after seizure and confiscation, physically inventory and photograph the same in the presence of the accused or the person/s from whom such items were confiscated and/or seized, or his/her representative or counsel, a representative from the media and the Department of Justice (DOJ), and any elected public official who shall be required to sign the copies of the inventory and be given a copy thereof[.]